A Copper‐Benzotriazole‐Based Coordination Polymer Catalyzes the Efficient One‐Pot Synthesis of (N′‐Substituted)‐hydrazo‐4‐aryl‐1,4‐dihydropyridines from Azines

Abstract

As eries of new (N'-substituted)-hydrazo-4-aryl-1,4-dihydropyridinesw as successfully synthesized via af acile one-pot catalytic pathwayu tilizing azines andp ropiolate esters as starting materialsa nd ao ne-dimensional copper benzotriazole-based coordination polymer as catalyst. In the absence of catalyst, the corresponding 5-substituted 4,5-dihydropyra-zoles were formed in moderate to high yields.F inetuning of the catalysts allowed us to gain more insights regarding the plausible reactionmechanism.Scheme2.Plausible mechanism for the synthesis of the (N'substituted)-hydrazo-4-aryl-1,4-dihydropyridines throught he hydrazine and propiolate Cu-catalyzed coupling.

Selective Reduction of Azines to Benzyl Hydrazones with Sodium Borohydride Catalyzed by Mesoporous Silica‐Supported Silver Nanoparticles: A Catalytic Route towards Pyrazole Synthesis

“…), were proved to be efficient catalysts,a ffording hydrazone 1a in moderate to excellent yields (41-99%), within short reactiont imes 10-60 min ( Table 2, entries 4, 6-9). Thus we assume that the present reductionp roceeds mainly on the AgNPs which appears to favour the 1,2-selective reduction, forming exclusively 1a ( Table 2, entries [4][5][6][7][8][9]. In the absence of silver catalyst no conversion of 1 to 1a was observed evena fter ap rolonged reactiont ime;h owever, the 1b derivativew as formed and determined by 1 HNMR (Table 2, entry 10).…”

“…[1,2] These acyclic 1,3-heterodienes were found to displayad iverse range of pharmacological andb iological activities. [1] Recently,t hey have attracted interest as precursors for the synthesis of 1,4-dihydropyridines, [7] 1,3,4-oxadiazoles, [8] pyrazoles [9] and various heterocycles. [1] Recently,t hey have attracted interest as precursors for the synthesis of 1,4-dihydropyridines, [7] 1,3,4-oxadiazoles, [8] pyrazoles [9] and various heterocycles.…”

Sulfonated Caspian Sea Sand: A Promising Heterogeneous Solid Acid Catalyst in Comparison with –SO3H Functionalized NiFe2O4@SiO2@KIT‐6

“…Although the classical Hantszch method is a straightforward route for preparation of 1,4‐dihydropyridines from β‐ketoesters, an aldehyde and ammonia, there are several modifications for this method to facilitate the synthesis of other substituted 1,4‐dihydropyridines. These include the use of enamines in presence of either aldehydes or ketones, reduction of pyridine and pyridinium salts in presence of metal‐hydrides, condensation of α,β‐unsaturated carbonyl compounds with active‐methylene compounds and amines, and multi component condensation of 1,3‐dicarbonyl compounds with aldehydes and NH 4 OAc, in presence of a wide range of homogeneous and heterogeneous catalysts . Also, 3,4‐dihydropyrimidin‐2( 1H )‐ones as analogs of 1,4‐dihydropyridines, play significant biological roles such as antibacterial, antioxidant, anti HIV and anticancer.…”

A 12-Fold ThSi2 Interpenetrated Network Utilizing a Glycine-Based Pseudopeptidic Ligand

“…Encouraged by the obtained result, we opted to investigate this effect on additional pseudopeptidic ligands. Having also in mind (a) our ongoing interest on CPs and their catalytic properties [32][33][34] and (b) the commonly limited solubility of these bulky pseudopeptidic CPs in organic solvents, we theorized that the resulting compounds could have an interesting activity as heterogeneous catalysts. Therefore, we herein present the synthesis, characterization, and topological evaluation of a novel compound formulated as [Cu3(L 1 )2(H2O)8]·8H2O (1), where H3L 1 is N,N′,N′′-tris(carboxymethyl)-1,3,5-benzenetricarboxamide [35], also commonly known as trimesoyl-tris-glycine (Scheme 2).…”